Production of magnesium.



UNITED STATES PATENT OFFICE.

GEORGE O. SEWARD AND FRANZ VON KI TGELGEN, OF HOLOOMBS ROCK, VIRGINIA.

PRODUCTION OF MAGNESIUM.

Specification of Letters Patent.

Patented Oct. 15, 1907.

Application filed October 25, 1905, Serial No. 284,308. Renewed August 22,1907. Serial No. 389,723.

To all whom it may concern:

Be it known thatwe, GEORGE O. SEWARD, a citizen of the United States, and FRANZ Von KI'JGELGEN, a subject of the German Emperor, both residing at Holcombs Rock, Bedford county, Virginia, have jointly invented certain new and useful Improvements in the Production of Magnesium, of which the following is a specification. i

. Magnesium is at present produced by the electrolysis of a fused mixture of magnesium chlorid (MgGl and an alkali chlorid, as K01. The aim in this process is to have the specific gravity of the electrolyte so low that the separated magnesium will sink to the bottom readily. There is, however, no suitable flux which can be used and which will so lower the specific gravity of the electrolyte that the result desired may be obtained to any satisfactory extent,this on account of the lightness of the metal magnesium.

We adopt the opposite course, which is to add such flux es that the specific gravity of the electrolyte is so V much greater than that of magnesium that the separated metal will float readily on the electrolyte and is collected at the top instead of at the bottom of same.

)Ve have discovered that the fluoride of metals more electro-positive than magnesium, are peculiarly adapt ed to increase'the specific gravity of a magnesium chlorid electrolyte. We .prefer to use the fiuoridspi the earth alkali metals, as we get the desired heavy electrolyte by addition of a small percentage of these fiuorids. The

process may be carried out as fo11ows:-To.a molten mixture of MgOl and an alkali chlorid, about 6 per cent. fluorspar is added. I This dissolves in the electrolyte and makes the same so heavy that the magnesium,

separated the electrolysis of the molten mixture,

rises readily-to the top. Barium-fluorid may be sub-V stituted for fluorspar if desired.

of detail certain specific We are aware that fluorspar has been used as a flux, but never for the purpose of making the electrolyte heavier than the separated'metal, and never in such 40 Though we have-described with great particularity processes embodying the invention, yet it is not to be understood that the invention is limited to the specific processes described. Various modifications thereof may be made by those skilled in the art without departure from the invention.

What we claim isz- 1. In producing magnesium electrolytically, the process which consists in the addition to the electrolyte of so much of a arated magnesium.

2. In the electrolytic production of magnesium, the process which consists in the addition to the electrolyte of so much of an alkali-earth-fluoridthat the electrolyte be comes heavier than the separated magnesiuml 3. The process of producing magnesium, which consists informing a molten mixture of magnesium chlorid and alkali chlorid, and so much of a fluorid ofj a metal more electro-positive than magnesium that the electrolyte becomes heavier than magnesium, nesium by electrolysis.

4. The process of producing magnesium, which consists informing a molten mixture of magnesium chlorid, an alkali chlorld, and about 6 per cent. of fiuorspar, whereby and separating the mag-5 the electrolyte becomes heavier than magnesium, and sep- 7Q arating the magnesium byeiectrolysis.

In witness whereof, we have hereunto signed our names in the presence of two subscribing witnesses.

GEORGE 0. SEWARD. l V 1 .ERANZ you KUGELGEN. Witnesses:

' 'JLHHWEBB, C. Orrnnnnus. 

